The intent of this proposed research is to isolate, characterize chemically, identify known constituents and determine the structure of unknown constituents of Porophyllum lanceolatum DC. that are inhibitory to various strains of Mycobacterium tuberculosis, M. smegmatis and Candida albicans. A quantitative study of the antibiotic activity will be carried out. In addition, the toxicity of the active components as well as untoward pharmacological activity will be determined in order to establish the therapeutic merit and safety as a drug.